1. Field of the Invention
This invention relates to a crossband device for an automobile tire, which is attached to the automobile tire to prevent tire slips during travel on snow-covered roads.
2. Description of the Prior Art
In a prior application, Japanese Patent Application 63-155675, the present inventor proposed an anti-slip crossband device of this sort, which is composed of a main body detachably attachable to the outer side of an automobile wheel, a plural number of leaf springs operable to turn in both forward and reverse directions about the respective axes and extended radially outward from the main body, and anti-slip crossbands attached to the fore ends of the leaf springs to lie in abutting contact with the tread surface of the tire to prevent slips. When driving on a snowy road, this cross-band device is attached to the outer side of an automobile wheel, and the crossbands are brought into abutting engagement with the tread surface of the tire by turning the leaf springs. When not used, the crossbands are displaced into receded positions away from the tread surface by turning the leaf springs, and then the crossband device is removed from the automobile wheel and put away in a folded state in a trunk room or other suitable place on the vehicle.
The above-described crossband device has advantages that it can be easily attached to the outer side of an automobile wheel by the use of wheel nuts and that, when not necessary, it can be removed from the wheel and folded into a compact form suitable for storage in a trunk room of the vehicle. However, it is arranged to turn the leaf springs in forward and reverse directions by a handle operation through a gear mechanism, which is complicated in construction, troublesome to manipulate, and high in production cost.
Further, it is important for a crossband device of this sort to take into account the variations in tire diameter which occur during travel of a vehicle due to flexing of the ground-contacting portion of the tire, as well as the displacements of the crossbands in the circumferential direction along the tread surface at the ground-contacting portion of the tire.